760Piperacillin/Tazobactam-Induced Adverse Drug Events in Pediatric Patients on Outpatient Parenteral Antimicrobial Therapy (OPAT)

Background. Piperacillin/tazobactam is an ureidopenicillin (piperacillin) combined with a ß-lactamase inhibitor (tazobactam). We have noted an increased rate of suspected piperacillin/tazobactam-related adverse drug events (ADEs) compared to other antibiotics in patients on Outpatient Parenteral Antimicrobial Therapy (OPAT). We sought to compare ADEs in patients who received piperacillin/tazobactam vs other antibacterial agents. Methods. Patients (< 18 years of age) who received antibacterial agents as OPAT from January 2010-December 2012 were included. Data collected included demographics, clinical features and ADEs documented during therapy (including abnormal signs/symptoms and abnormal lab values) and considered to be antibiotic-related if there was no other explanation along with resolution of symptoms or normalization of lab values upon discontinuation of the antibiotic. Results. 106 patients (age range 2 months-17.9 years; median 10.5 years; 61 males) met inclusion criteria. 38 patients received piperacillin/tazobactam vs 68 patients received other antibacterial agents. The most common diagnoses treated with OPAT were perforated appendicitis (29%), pneumonia (18%), and osteomyelitis (13%). Of those who received piperacillin/tazobactam, 15 patients (39%) developed ADEs [most commonly fever (73%), transaminitis (67%), leukopenia (67%), neutropenia (67%), rising ESR and CRP (67%)] abdominal pain (40%), rash (20%), and vomiting (20%)], vs 3 patients (4%) who received other antibacterial agents (p = <0.001). 80% of patients had ADEs that included a constellation (3 or more) of clinical and laboratory features with a median time-to-ADEs of 17 days (range 7-23). 67% of patients with ADEs were hospitalized with a median length of stay of 4 days. Conclusion. Patients receiving piperacillin/tazobactam in OPAT had a significantly increased risk of ADEs compared to other antibacterial agents. These events often manifested with a constellation of clinical findings that frequently were thought to be related to the primary diagnosis rather than ADEs, and often resulted in re-hospitalization and a change or cessation of therapy. Disclosures. All authors: No reported disclosures.